An alanine-to-proline mutation in the BB-loop of TLR3 Toll/IL-1R domain switches signalling adaptor specificity from TRIF to MyD88.

ABSTRACT: A functionally important proline residue is highly conserved in the cytosolic Toll/IL-1R signaling domains of human TLRs. The antiviral Toll, TLR3, is unusual because it has alanine instead of proline at this position and is the only human TLR that associates directly with the adaptor molecule TIR domain-containing adaptor inducing IFN-β (TRIF) rather than MyD88. In this article, we report that a mutant TLR3 that substitutes the BB-loop alanine for proline (A795P) enhances NF-κB activation but is incapable of mediating TRIF-dependent IFN response factor 3 responses. Wild-type and A795P TLR3 associate constitutively with both TRIF and MyD88, and activation induces additional binding of TRIF to the wild-type and of MyD88 to the A795P mutant receptors, respectively. In addition, activation of

SUBMITTER: Verstak B 

PROVIDER: S-EPMC3858240 | biostudies-literature | 2013 Dec

REPOSITORIES: biostudies-literature